Hi! There is a thermodynamics problem which I seem to be able to understand, yet unable to solve. If someone can me with it I would appreciate it.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

A Bi-metallic strip is straight at T= T_{0}. It curves as it is heated up due to unequal expansion of two metals. The strip is made up of iron (a = 1.2e-5) and zinc (a = 3.1e-5). The question asks to calculate the bending angle when the original length of the strip is 100mm and with thickness of 1 mm.

2. Relevant equations

The linear expansion equation: L = L_{0}(1 + a(T_{2}- T_{0}))

3. The attempt at a solution

The substituted equations: L_{I}= (100)(1 + (1.2e-5)([tex]\Delta[/tex]T)

L_{Z}= (100)(1 + (3.1e-5)([tex]\Delta[/tex]T)

From here I use the formula s = r[tex]\theta[/tex]

and get [tex]\theta[/tex] = (3.8e-3)([tex]\Delta[/tex]T)

I am not sure how to proceed from here because the question asks for a numerical answer but that seems impossible without the temperatures given.

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# Homework Help: Bimetallic Strip Bending Angle

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